When accessing different services, users are often required to authenticate themselves by providing credentials such as a username and password, or by presenting a token such as a health care card. In some situations, to prevent unauthorized access, a user is required to present a token and enter a password. For example, when accessing a bank machine, a user is required to present a bank card and a secret personal identification number (PIN).
With the increasing number of services available online or through electronic databases, and the growing ubiquity of mobile devices, it would be advantageous to provide a system for authorizing access to a service using mobile devices.
Like reference numerals are used in the drawings to denote like elements and features.